ABSTRACT This is a NIH Pathway to Independence Award (K99/R00) grant proposal, intended to promote the career of Dr. Christy Avery, PhD, a post-doctoral fellow at the University of North Carolina, into a path of independent research. The Candidate is a trained epidemiologist with a significant track record of research in the field of cardiovascular disease epidemiology. Her goal is to integrate these skills with focused training in clinical research to become an independent scientist at the interface of basic science, clinical practice, and population research. The topical area for the proposed experiential development is translational research in heart failure. During the mentored K99 phase the Candidate will expand her clinical research skills by interacting with clinical specialists who are productive scientists in heart failure research, engaging in formal didactics, attending multidisciplinary seminars, journal clubs, and scientific meetings, participating study activities with her mentors, and by leading a project that develops novel heart failure classification tools applicable to clinical practice and population research. These activities will be supervised by mentor Dr. Gerardo Heiss MD PhD, Kenan Professor of Epidemiology and co-mentor Dr. Patricia Chang, MD MHS FACC, Assistant Professor of Medicine. In addition, a team of collaborators with complementary areas of expertise will supplement Dr. Avery's training in specific areas. Together, the mentor, co-mentor, and collaborators are fully committed to assisting the Candidate reach her research training and career development goals and to ensuring the Candidate's successful transition from postdoctoral fellow to independent researcher. During the independent R00 award phase, the Candidate will apply the tools developed during the K99 component in the cohort of the ongoing Atherosclerosis Risk in Communities (ARIC) Study. For this purpose the ARIC study investigators are making available data on the cohort's follow-up calls, their physician visits, emergency department visits and hospitalizations, and the associated diagnoses. This information base will be combined with outpatient and inpatient Medicare claims data and reports by participant's treating physicians to estimate the burden of heart failure and its patterns of diagnosis and care in ARIC Study participants. The Candidate also will characterize the transition from heart failure managed in outpatient settings to acute/decompensated heart failure events requiring hospitalization. The proposed research is both novel and of major potential for translation, with possible relevance for early diagnosis and proactive management of heart failure as well as for health services allocation and program evaluation. The short term benefits from this study will be a contribution to the under- studied area of quantifying the outpatient burden of HF and its secular trends in communities.